Among the sea of grey, blue and black suits were five female politicians – all democrats in their second term, just like Obama – sitting together wearing pink suits.

It was a powerful statement and not the "On Wednesdays we wear pink" kind, as the women all synced up outfits to not only celebrate women in power but to also show the lack of gender equality in the House of Representatives.

Cheri Bustos from Illinois, Julia Brownley from California, Lois Frankel from Florida, Katherine Clark from Massachusetts and Ann McLane Kuster from New Hampshire posed for photos in their blush ensembles before posting the image and blasting out their message on Twitter.

"Sophomores in pink-we need more women in Congress," Bustos said.

"Wearing pink at State of the Union to celebrate over 100 women in Congress! We need to elect more," Kuster posted.

"Wearing pink to #SOTU because need more women in Congress!" Brownley wrote.

In the US there are 403 men in congress and 104 women.

Comparatively in Australia there are 150 members of the House of Representatives, 37 of them are female.

Meanwhile, Michelle Obama made a sartorial statement of her own, either accidently or subliminally.

The first lady wore a tweed Michael Kors skirt suit featuring an off-the-shoulder jacket with exposed zip and knee length skirt. Fans of The Good Wife would have recognised the look because Julianna Margulies' character Alicia Florrick – a fellow lawyer from Chicago – wore the same ensemble in a recent episode.

Prior to his address, Mr Obama's assistant and senior advisor Dan Pfeiffer caused a stir on social media by suggesting POTUS was bringing his infamous tan suit out of retirement for one of the most important speaking engagements of his presidency.

He, much to the relief of the American public, instead took a leaf out of Tony Abbott's style handbook and donned a navy suit with ice blue tie.